Stencil-controlled automatic sewing apparatus



y 1967 H. ADAM ETAL 3,332,378

STENCIL-CONTROLLED AUTOMATIC SEWING APPARATUS 6 Sheets-Sheet 1 Filed April 27, 1965 7 I27 70 I29 29 I26 Fig.7

INVENTOR5 HA/vs 40AM? BY Flam/v2 SCH/V6705? A 7'7'OR/VEY July 25, 1967 H. ADAM ET AL STENCIL-CONTROLLED AUTOMATIC SEWING APPARATUS Filed April 27, 1965 6 Sheets-Sheet 2 Ill-nun INVENTORS lm/vs A 0A; A FR 4 NZ 5 c fi/VE/OEf July 25, 1967 H. ADAM ET AL 3,332,378

STENCIL-CONTROLIJED AUTOMATIC SEWING APPARATUS 6 Sheets-Sheet .3

Filed April 27, 1965 1 a M M July 25, 1967 D ET AL 3,332,378

STENCIL-CONTROLLED AUTOMATIC SEWING APPARATUS 6 Sheets-Sheet 4 Filed April 27, 1965 m. m $0 m ma v m 5 mM A W z w M 7 AM 4 F Y B July 25, 1967 H. ADAM ET AL STENCIL-CONTROLLED AUTOMATIC SEWING APPARATUS- 6 Sheets-Sheet 33 Filed April 2'7, 1965 Fig. 77

WMM 4 m 2 M 0 MM July 25, 1967 H. ADAM ETAL 3,332,378

STENCIL-CONTROLLED AUTOMATIC SEWING APPARATUS BY FRANZ SCHNEIDER A rronxvs Y United States Patent 3,332,378 STENCIL-CONTROLLED AUTOMATHI SEWING APPARATUS Hans Adam, Vaterstetten, near lt iunich, and Franz Schneider, Kaiserslautern, Pfalz, Germany, assignors to G. M. Pfatf A.G., Kaiserslautern, Pfa z, Germany, a corporation of Germany Filed Apr. 27, 1965, Ser. No. 451,134 Claims priority, application Germany, Apr. 29, 1964, P 34,147 14 Claims. (Cl. 112-2) The present invention relates to automatic sewing apparatus of the general type comprising a sewing goods or workpiece carrier having connected therewith a stencil driven in form-locking engagement by suitable drive means. The stencil may be constituted by a multiplicity of mutually spaced driving elements, such as gear-teeth forming a rack arranged along a guide path of predetermined shape or configuration and engaged by a pinion or the like driving element adjoining the needle or stitching point of a stationary sewing machine, said carrier being mounted for both translatory and rotary motion, in such a manner as to move the work upon the sewing goods carrier past the stitching point of the machine in varying directions in conformity with the configuration of the stencil guide path for the sewing of a corresponding pattern or seam upon the work being operated on.

In a known construction of automatic sewing apparatus of this type, the work is carried by a tentering frame a mounted for both translatory and rotative movement and being operated by a stencil in the form of a rack connected therewith and having a shape conforming to the configuration of the seam or pattern to be sewn by a stationary sewing machine. Cooperating with said rack is a driving wheel or pinion mounted at the upper end of a vertical drive shaft being disposed laterally of the needle of the sewing machine, in such a manner as to displace the frame and work carried therby in varying directions relative to the stationary stitching point in conformity with the configuration or shape of said rack, whereby to in turn result in the sewing of a seam of corresponding configuration. Apparatus of this general type, while allowing of the automatic sewing of straight and relatively moderately curved seams, that is, seams comprising corners or sections including angles in excess of 90 only, are unsuitable for the sewing of relatively sharp corners or acute angular sections forming part of a seam or pattern to be sewn.

Accordingly, an important object of the present invention is the provision of improved automatic sewing apparatus of the referred to type being capable of sewing seams of practically any desired shape or configuration, including seam sections representing relatively sharp corners or sections having relatively small radii of curvature which may be less than the radius of the driving pinion or equivalent driving element.

Another object of the invention is the provision of automatic sewing apparatus of this type being capable of sewing relatively sharp corners or acute angles forming part of the seam to be sewn.

Generally, the foregoing aims and objects of the invention are achieved by the provision of improved driving means for the stencil conforming to the seam or pattern to be produced, said driving means being constructed in a manner to enable the displacement of the stencil and, in turn, the sewing goods or work carrier along any desired path or trace substantially independently of the dimension of said driving means (driving pinion, etc.).

More particularly, with the foregoing and ancillary objects of the invention in view, as will become more apparent as the description proceeds, the improvement, according to one of the aspects of the invention, involves 3,332,373 Patented July 25, 1967 essentially the provision of a pair of opposed driving pinions engaging the opposite side of the stencil, one of said pinions (main driving pinion) being disposed coaxially with the needle or in registry with the stitching point of the sewing machine, while the other of said pinions (auxiliary driving pinion) is rotatively mounted upon a rotary support or turntable being coaxial with said first pinion, the spacing distance between the axes of said pinions being such as to allow both pinions, driven in opposite directions by an electric driving motor, being preferably the main driving motor of the sewing machine, to operatively engage, one at a time, the opposite sides of the driving elements of the stencil (rack teeth, pins, etc.), in such a manner as to cooperatively drive the latter within the relatively moderately curved and straight sections of the seam being sewn. In order, furthermore, to allow of the sewing of relatively sharp corners or curved seam sections representing angles of less than there is provided, in accordance with the present improvements, control means being disposed at the corner points of the stencil and operative selectively in diiferent vertical planes, in such a manner as to cause the point of engagement of the stencil driving elements with the driving pinions to change between an upper and a lower plane during the sewing of the corner sections or angles. Besides, in the lower engaging position of the pinion, the stencil drive is temporarily disabled, to allow the turntable carrying the auxiliary driving pinion to be rotated, to cause the latter to roll upon the main driving pinion and to be displaced from a position of engagement with one arm or leg of the angle or corner to a position of engagement with the other leg of said corner, that is, a position suitable for the commencement of the sewing of said last-mentioned leg by both pinions in the normal manner. On account of the change of the point of engagement of the driving pinion, the curved section of the guide path or stencil representing an angle or corner is enabled, both in the case of right and acute angles, to advance in one position of engagement of the driving pinion to a point coincident with the center of the main driving pinion being coaxial with the stitching point, on one hand, and to emerge from or run out of said pinion in the other position of engagement of the pinions, on the other hand. In other words, the laws governing the internal gear drive are temporarily suspended during the sewing of the corners in accordance with the concept of the invention, while maintaining an efifective form-locking engagement between the stencil and driving pinions, in such a manner that the radius of curvature of the guide path sections representing the angles or corners may be of any size and equal to the radius of the main driving pinion being coaxial with the needle. This, in turn, enables the sewing of clearly defined or sharp corners or acute angles, respectively, as will become further apparent as the description proceeds.

According to the preferred embodiment of the invention, to eifect the change between the points of engagement of the stencil and the driving pinion at the corner points of the seam or guide path, and to avoid the occurence of excessive covering angle liable to impede the entry of the curved stencil section into and emergence from the main driving pinion, the latter is displaceable in a vertical direction and the guide path or stencil is comprised of a multiplicity of mutually spaced rack pins or teeth, with the pins representing the corners of said path having a length in excess of the length of the remaining pins and being formed with suitable recesses of reliefs, in such a manner as to cause the main driving pinion, to engage, in the upper position, the points pertaining to one leg of the angle or corner, and to engage, in the lower position, the pins pertaining to the other leg of said corner, respectively, in the manner described iii greater detail hereafter.

In the manufacture of gentlemens collars, in particular one-piece collars, it is often necessary to sew or stitch both so-called inner and outer corners of the collars. Since the auxiliary driving pinion must be, for the sewing of a corner in the manner described, at the proper side of the seam being sewn, suitable changeover or reversing means are provided, according to an improved feature of the invention, between two successive corners of different type, to displace the auxiliary pinion by 180 or from one side to the other side of the main driving pinion, to enable the subsequent sewing of a corner being different in type from the preceding corner. For the latter purpose, it is necessary for the stencil at the changeover points to change from one to the other side of the seam.

According to another embodiment to accomplish the latter object, dual driving means adapted to selectively cooperate with different stencil portions or sections may be provided to result in the automatic sewing of both inner and outer corners without any changeover or displacement of the auxiliary driving pinion. According to a preferred embodiment, there is provided for this purpose a second pair of driving pinions comprising a further main driving pinion being coaxial with the needle or the first driving pinion, respectively, both said main driving pinions being driven in opposite directions, and a further auxiliary driving pinion mounted upon the turntable in a manner similar to the first auxiliary driving pinion, both said auxiliary driving pinions also being driven in opposite directions, and means to control the point of engagement of said pinions with the stencil driving elements, in such a manner as to cause both pairs of driving pinions to selectively operate, respectively, for the automatic sewing of the straight or relatively slightly curved sections of the seam and for the sewing of either inner and outer corners, substantially without the use of any special changeover means or operations. In other words, the different pairs of driving pinions serve or are automatically selected for the driving of the stencil depending upon the character of the corners or angles to be sewn, in the manner more fully explained and described in the following.

The turntable carrying the auxiliary driving pinion or pinions is advantageously fitted at its lower end with a set of driving gear teeth being driven, by way of a counter gear and a suitable overload coupling, by an auxiliary electric motor which is controlled by a switch and actuator carried by the stencil, the effect of the overload coupling in arresting the drive by the auxiliary motor resulting in the rotation or displacement of the auxiliary pinion over the limited varying angular paths, depending upon the size or angle of the corners being sewn.

The invention, both as the foregoing and ancillary objects as well as novel aspects thereof, will be better understood from the following detailed description, taken in conjunction with the accompanying drawings forming part of this specification and wherein:

FIG. 1 is a general assembly elevational view of a sewing machine embodying stencilcontrolled automatic sewing apparatus constructed in accordance with the principles of the invention;

FIG. 2 is an enlarged partial view of the stencil drive mechanism of FIG. 1, shown partly in section;

FIG. 3 is a schematic view showing, by way of example, a stencil guide path in the form of a pin rack and embodying a dual pinion drive according to the invention, the seam to be sewn indicated by the dashed line in the drawing;

FIG. 4 is a section taken on line IV-IV of FIG. 3;

FIG. 5 is a section taken on line VV of FIG. 3, showing the parts in a first operative position;

FIG. 6 is a section similar to FIG. 5, showing the parts in a subsequent operative position;

FIG. 7 is an enlarged view similar to FIG. 2, showing, partly in section, a modified stencil drive mechanism according to the invention;

FIG. 8 is a schematic view of a pair of stencil guide paths for use in connection with the modified drive of FIG. 7;

FIG. 9 is a sectional view taken on line IX-IX of FIG. 8;

FIG. 10 is a perspective view of a modified stencil construction according to the invention;

FIG. 11 is a top view of a stencil according to FIG. 10, including its operating driving pinion pair;

FIG. 12 is a sectional view taken on line XII--XII of FIG. 10;

FIG. 13 is a sectional view taken on line XIIIXIII of FIG. 19 and including the driving pinion pair of the invention, and

FIG. 14 is a wiring diagram of the control apparatus according to FIGS. 2 or 3.

Like reference numerals denote like parts throughout the different views of the drawings.

Referring more particularly to FIG. 1, the frame of a conventional sewing machine supports a base plate or bed 2 having secured thereto an upright 3 from which extends an overhanging horizontal arm 5 terminating in the sewing head 4. Mounted within the arm 5 is the main operating or arm shaft 6 of the machine being driven, by way of a belt 7 and a pair of pulleys 8 and 9, from the main driving motor 11} mounted upon the frame 1 and serving, among others, to operate the reciprocatory needle bar 12 mounted in the head 4 and carrying the needle 11, in a manner well known and understood by those skilled in the art.

Mounted upon the arm or drive shaft 6 is a further pulley 13 which serves to drive, by way of a belt 14 and counter puiley 15, a shaft 16 mounted in the bed 2, said last shaft carrying at its front end the loop taker 17 cooperating with the needle 11 in the formation of lockstitches in the ordinary manner.

Secured to the undersurface of the table top 18 of frame 1 are a pair of mounting brackets 19 in which are secured, by means of screws 22, a pair of guide bars 21 forming a rectilinear guide 29. Displaceably mounted upon the bars 21 or guide 20 is a carrier member 23 wherein in turn is mounted a freely rotatable hollow vertical shaft 24 secured in the axial direction by a pair of setting rings 25. Secured to the lower end of the shaft 24 is the operating stencil 26 comprising a carrier or supporting plate 27 fitted upon its undersurface with a multiplicity of depending pins 102 (see also FIGS. 2 and 3) disposed in uniformly spaced relation and forming a pin rack or workpiece operating stencil constituting a guide 29, FIG. 3, for the operation or control of the sewing goods carrier and feeding of the workpiece past the stitching point or needle 11, in the manner further understood as the description proceeds.

Operation of the stencil 26 is effected by the driving motor '10 of the sewing machine by way of a further pulley 30, a belt 31, counter pulley 32 and input drive shaft 33 of a speed reduction gear unit 35 supported by an intermediate wall 34 of the frame 1. The reduction unit 35, which furthermore includes means (not shown) for the reversal of the direction of rotation of the output shaft 39 for the purpose to be described presently, is operably connected with an electric contact device 37 supported by a bracket 36 and adapted to cooperate with a cam or actuator 38 affixed to the stencil carrier or supporting plate 27, to effect a reversal of the direction of rotation of the output drive shaft 39 of the unit 35 upon actuation of the device 37 by the cam 38, in the manner described in greater detail in the following.

Mounted upon the output shaft 39, FIG. 2, of the speed reduction unit 35 is a worm 4t) driving, by way of a worm gear 41, a hollow vertical shaft 44 being journalled in an intermediate wall 42 of a casing 43 supported by frame 1. Shaft 44 is secured axially by the worm gear 41, on the one hand, and by a coupling member 45 secured to its lower end, on the other hand. Memher has a flange provided with a pair of radial recesses 46 into which project a pair of coupling pins 48 secured to a follower or coupling ring 47, to effect coupling and decoupling between said ring and shaft, respectively. Secured to ring 47 is a further hollow drive shaft 49 being journalled within the shaft 44, the upper end of shaft 49 being, in turn, journalled in a turntable or support 50 which is freely rotatably mounted in the casing 43 and carries a pin at its upper end to which is secured the main stencil driving gear or pinion 52 in line or coaxial with the needle 11. Further secured to the pin 51 below the pinion 52 is a gear 53 meshing with a counter gear 54 having the same pitch diameter as gear 53 and mounted upon a sleeve 55 which is freely rotatable about a further pin 56 mounted in the turntable 50. Sleeve 55 at its upper end carries an auxiliary driving gear or pinion 57 cooperating with the pinion 52 and pin rack or stencil 26 in the manner described in greater detail hereafter. In the example shown by the drawings, with the driving stencil taking the form of a pin rack, both pinions 52 and 57 are arranged to engage with their opposed gaps one of the pins of said rack at a time in operating or advancing the stencil (see FIG. 3).

Coupling ring 47 has a circumferential groove 58 being engaged by a pair of opposed rollers 59 mounted upon the fork-shaped end 60 of a double-arm lever 61 which is pivoted about a horizontal bolt 63 secured to the casing 43. The opposite arm of lever 61 is linked to the lower end of a vertically adjustable pull bar 64 to the upper end of which is in turn linked to one arm 65 of a further lever 65 pivoted about a bolt 68 secured to the casing 43. The opposite fork-shaped arm 67 of the lever 66 carries a pair of rollers 69, FIG. 1, engaging a circumferential groove 70 in turntable 50, the later being both rotatively and axially displaceably mounted in the casing 43.

Secured to the lower plane end surface of the coupling ring 47 is a depending lug 71 which is connected, by way of a pin 72, with the fork-shaped head 74 of the pull rod or bar of an electromagnet or solenoid 75, said head having a pair of slots 73 engaged by said pin and said solenoid being mounted upon the base of the casing 43. Similarly supported by said casing and adjoining the solenoid 75 is a further solenoid 76 having a push rod or bar 77 adapted to cooperate with an abutment 78 of the lever arm 62. The sense of operation of the solenoids 75, 76 is opposed with respect to one another, that is, magnet 75 upon energization is effective in the downward direction and magnet 76 upon energization is effective in the upward direction, as indicated by the arrows in the drawing, against the action of a spring connected to the intermediate wall 42 of the casing 43, on the one hand, and to the lever 61, on the other hand, and acting to urge both the coupling ring 45 together with the drive shaft 49 and turntable 50in an upward direction, to cause said table to engage the undersurface of the casing cover 43 in the normal or starting position shown in FIG. 2.

In order to effect rotation of the turntable 50, the latter has its lower part fitted with gear teeth 80 meshing with a counter gear 82 which is freely rotatively mounted upon a vertical shaft 81. Gear 82 is disposed upon shaft 81 between a setting ring 83 and a follower or coupling disk 84 in radially fixed but axially slidable connection with the shaft 81. Disk 84,, being fitted upon one of its end surfaces with coupling teeth 85 adapted to cooperate with similar teeth 86 upon the end face of the gear 82, is normally urged in the direction towards the gear 82 by the action of coil spring, intervening between said disk and a further disk secured to shaft 81, to provide an overload coupling 87 as described in greater detail in the following. Shaft 81 carries at its lower end a further coupling disk 89 being fixedly connected thereto and embraced by an electromagnetic coupling winding 90 mounted upon an intermediate wall of the casing 43. Journalled in the casing below the shaft 81 is a further drive shaft 91 being in driving connection, by way of a gear pair 92, 93, with a continuously rotating auxiliary electric motor 94 mounted upon the base of casing 43.

Secured to the drive shaft 91 is a sleeve 95 having longitudinal grooves 96 wherein is mounted in axially sliding relation a magnetic coupling disk 97, the latter serving to effect coupling connection between the shafts 91, 81 by cooperation with the disk 89 upon energization of the winding 90. In order to effect an automatic decoupling of the shafts 91, 81, upon operation of the overload coupling 87, the follower disk 84 of the coupling 87 is fitted with a circumferential groove 98 being engaged by the end of a two-arm lever 100 pivoted upon a carrier or bracket 99. The remaining arm of the lever 100 cooperates with an electrical contact device 101 which serves, upon actuation, to sequentially interrupt the circuit of the magnet winding 90, to close the circuit of the main driving motor 10 by way of a first time-delay relay, and to open the' circuit of the solenoid 75 through a further time-delay relay, respectively, in the manner and for the purpose described in greater detail hereafter.

The pins 102 forming the guide path 29 or driving stencil, FIG. 3, are arranged at equal distances corresponding to the pitch or semi-circular gaps of the driving pinions 52, 57, in such a manner that, as a result of the coaxial arrangement of the needle 11 and main driving pinion 52, the line connecting the centers of the pins 102 forms a curve or trace (guide path 29) displaced by a lateral distance equal to the radius of the pinion 52 from the seam or sewing pattern to be produced, as shown by the dashed line in FIG. 3. The pins 103 and 104 forming the corners of curved sections of the stencil 26 have a length about twice the length of the remaining pins 102, or thickness of the pinions 52, 57, respectively, the pins 103 representing the leading portion of said sections being formed at their lower halves with inner flats or reliefs 105 and the pins 104 forming the trailing portion of said sections being formed at their upper halves with flats or reliefs 106, FIG. 4, whereby, with a curved or corner section of the stencil entering and engaging the main driving pinion 52, the latter will be in engagement with the leading pins 103 only in its upper or normal position, and will be in engagement with the trailing pins 104 only in the lowered position, respectively, for the purpose which will become more apparent from the following description of the operation of the invention.

Mounted upon the top surface of the stencil carrier 27 at points adjoining or corresponding to the corners of the seam or guide path 29 is a cam or actuator 111 adapted to cooperate with a stationary electric contact device 113 supported by a bracket 112. Upon actuation, the device 113 acts to sequentially arrest the driving motor 10 with the needle in the work or DOWN-position, to energize the solenoid 75 through a first time-delay relay, and to subsequently energize the coupling winding 90 through a second time-delay relay, respectively.

In order to enable the successive sewing, by the use of apparatus according to the invention, of both inner and outer corners, or inwardly and outwardly oriented angles in respect to a given (straight) seam section, the pins 102, FIG. 3, are arranged alternately on the opposite sides of the seam or guide path 29, as shown at position II, FIG. 3, it being immaterial whether the main driving pinion 52, being coaxial with the needle of the sewing machine, is located on one or the other side of the stencil or guide path, as will be understood. The changeover point II may be located at any desired point between a pair of successive corners or angles, that is, upon any point of the intermediate seam section, in the case of FIG. 3.

More specifically, there are provided at the changeover point two pins 107 and 108 at the opposite sides of the seam the distance of the centers of which equals the diameter of the main driving pinion 52, as shown in FIG. 3. Pin 107 has a length about equal to twice the length of the pins 102 or the thickness of the pinion 52, whereas pin 108 has a length about three times said thickness (see FIGS. and 6), the upper third of the pin 108 being provided with a relief or fiat 109. The pin 110 following the pin 108 also has a length three times the thickness of the pinion 52, while the next following pins 102 of the guide path 29 are of normal length. Disposed at a point upon the upper surface of the stencil carrier 27, adjoining a changeover point II upon the guide path 29, is a cam or actuator 114 adapted to cooperate with an electric contact device 116 supported by a bracket 115, said device being operative, upon actuation, to sequentially interrupt the operating circuit of the motor 10, to close the circuit of the solenoid 75 by way of a first time-delay relay, to reverse the direction of rotation of the motor 94, and to close the circuit of the coupling winding 90, respectively.

The hollow shaft 24, FIG. 1, jou-rnalled in the carrier 23 has secured to its upper end, traversing a slot-like recess 117 in the table top 18, a plate 118 supporting the work or sewing goods to be opera-ted on and having, in the example shown, a contour conforming to the contour of the work, whereby to feed the work past the stitching point or needle 11 along a path determined by the configuration of the stencil 26 or guide path 29. In order to secure or retain the work upon the plate 118, there is provided a further retaining plate 119 also conforming, in the example shown, to the contour of the work and being maintained in engagement with the plate 118 by means of a pair of springs 120, in the manner shown and readily understood. The edge or part of the work projecting beyond the edges of the plates 118, 119 rests upon a socket 121 located at the stitching point and mounted in the bed 2 of the sewing machine, the edge of the work being further maintained in position during the sewing operation by means of a periodically operated presser foot 122.

In order to lift the upper supporting plate 119, for the insertion and removal of the work, said plate has a depending shaft or rod 123 passing through the shaft 124 and the plate 118. The lower end of the rod 123 terminates in a semi-circular member 124 arranged to cooperate with one arm 125 of a two-arm lever 126. The latter is pivoted upon the casing 43 about a pin 129 secured to a bracket 128 and carries at its opposite end 127 a pull bar or rod 130 which terminates in a foot pedal (not shown) or the like control member operation of which will result in the rod 123 being displaced in the upward direction for the lifting of the plate 119. While the work supporting plates 113, 119 conform, in the example shown, to the configuration of the work with the edge of the latter projecting beyond the edges of said plates for the carrying out of an edge seaming operation, the sewing goods carrier may be in the form of a tentering or the like frame holding the work piece or fabric for the sewing of a pattern or seam of desired configuration corresponding to the shape of the stencil 26 or guide path 29, in a manner readily understood.

The function and operation of the apparatus shown by FIGS. 1-6 will now be described in greater detail in the following.

Let it be assumed that it is desired to sew a seam in the direction of the arrow as shown by the dashed line in FIG. 3 and that, furthermore, a workpiece has been inserted between the plates 118, 119 and that the contacts of the various contact devices or switches are in the normal or starting position as shown in FIG. 14.

Operation of the starting switch S1 results in the energization of the relay D1 by way of its holding contact d10, whereby to close the circuit of the motor by way of contacts @311, d21, r131, d51, d61, relay C3 and switch S3, to start rotation of the motor. Coupled mechanically, as indicated by the dashed line in FIG. 14, with switch S1 is a further switch S2 which serves to energize a relay D8 by way of contacts [22 and d71, said relay being maintained in energized condition by a holding contact 6180 and serving to energize, by way of contact d8 a magnetic coupling winding K1 operably embodied in the speed reduction or gear unit 35. At the same time, a safety contact r181 of relay D8 inserted in the circuit of relay D7 is opened, to ensure that the output shaft 39 of the unit 35 rotates in the proper direction, that is, that the alternative coupling K2 of the reduction unit is in de-energized condition. During the sewing of the first section of the seam, both pinions 52, 57 are driven in opposite directions, whereby to engage with their opposed gaps the pins 102 of the guide path 29 or stencil 26, one at a time, to thereby drive the stencil in form-locking engagement with said pinions. As a consequence, the stencil, together with the hollow shaft 24 journalled in the carrier 23, rotates in accordance with the trace of the guide path formed by the pins 102, while said carrier is simultaneously subjected to a linear movement along the path 20, in such a manner as to effect the movement or displacement of the stencil 26 in polar coordinate fashion and to, in turn, feed the workpiece mounted between the plates, 118, 119 past the stitching point or needle 11 of the sewing machine, in accordance with the elemental polar coordinate component feeding movements of said stencil. During this operation or sewing of the respective seam section, the solenoids 7S and 76, as well as the magnetic coupling winding are in de-energized condition, whereby to maintain the turntable 50 in its normal or upper position, FIG. 2, by the action of the spring 79 and to cause the shaft 81 to be decoupled from the drive shaft 91. As a consequence, the turntable 50 is freely rotatable, to thereby enable the driving pinion 57, aside from the rotation about its own axis, to freely rotate about the axis of the turntable 51 or pinion 52, respectively. As a result of this freedom of rotation of the pinion 57, the latter is enabled to assume, on the basis of the laws of engagement of rotating gear mechanisms, a position at any point of the guide path 29 such that the connecting line of the centers of the pinions 52, 57 will be at right angle to the tangent of said path at the engaging point, whereby to make it possible to operate with stencil sections having a radius of curvature less than the radius of the driving pinion 52.

While the pinions 52, 57 cooperating with the stencil 26 are at a fixed position relative to the needle 11 or stitching point of the sewing machine, to result in the displacement of the stencil or feeding of the work in accordance with the seam or sewing pattern to be produced, the stencil 26 composed of the pins 102, 103 and 104, FIG. 3, is shown to be stationary in the drawing and the pinions 52, 57 are repeated at various relative operating positions or points I, II and III of the seam or guide path, for ease and simplicity of illustration.

As soon as the section of the stencil or guide path 29 representing the first corner or angle of the seam reaches the driving pinions 52, 57, and after the curved section of the guide path or stencil has embraced the pinion 52 in the manner shown at position I of FIG. 3, the electrical contact device 113 actuated the cam 111, which is disposed upon the upper surface of the stencil carrier 27, operates a relay D6 which is maintained in energized condition by its holding contact (160. As a consequence, contact D61 of the relay D6 is opened, whereby to in turn open the relay C3 and to arrest the motor 10 with the needle 11 in the work or DOWN-position. At the same time, actuation of the contact device 113 has set in operation, by way of contact d62, the two timedelay relays D11 and D12. Since the pins 104 of the trailing leg or corner section are provided with reliefs 106, as shown in FIGS. 3 and 4, and since the driving pinion 52 is accordingly decoupled or disengaged from the pins 104, the curved section of the guide path or stencil 26 representing the seam corner or angle, is enabled to engage the pinion 52 to a point where its radius of curvature coincides with the rotary axis of pinion 52, or axis of the needle 11, respectively.

Actuation of the contact device 113 further causes, by way of contact d111 of the time-delay relay D11, the energization of the solenoid 75, whereby the forked head 74 of said solenoid connected to the follower ring 47, together with the drive shaft 49, pull bar 64 and turntable 50, are displaced, by way of levers 61 and 66, in the downward direction to an extent equal to the thickness of the pinions 52, 57. At the same time, closing of the contact [1121 of time-delay relay D12 causes, by way of contacts c141 and d121, the energization of the magnet winding 90, on the one hand, as Well as the energization of the relay C1 and, in turn, of the auxiliary driving motor 94 by way of contacts c141, d121, (163, 021 and switch S1, on the other hand. Relay C1 has a safety contact 011 connected in the circuit of the relay C2, to ensure the circuit of the relay to be interrupted if the circuit of C1 is closed, and vice versa, whereby motor 94 is securely rotated in the desired or predetermined direction. Both shafts 81 and 91 are coupled by the action of winding 90, whereby to cause the turntable 50 together with the pinion 57 to be operated by way of the overload coupling 87 and gear 82 such as to rotate in the direction as indicated by the circular arrow at position I in FIG. 3, while the pinion 52 is at rest due to the stoppage of the motor 10. In other words, the driving pinion 57, rotating about the axis of the turntable 50 or pinion 52 and rolling upon the pins 103, 104 is displaced from a position of engagement with the leading leg of the angle forming the seam corner (pins 103), as shown in full lines in the drawing, to a position of engagement with the trailing leg of said angle (pins 104) as shown by dot-dash lines in the drawing, respectively. Pinion 52 at the end of the downward displacement of the turntable 50 engages the pins 104 or the trailing leg of the angle only, while the pinion 57 rolls upon the pins 103, 104, to thereby maintain a continuous form-locking engagement between the stencil and driving pinions both during and at the end of the downward movement of the turntable.

The pinion 57 in the end position, as indicated in dotdash lines at point I in FIG. 3, is enabled to continue its rotations to a relatively slight extent only while engaging the stencil, in such a manner as to be arrested in cooperation with the pinion 52 being at rest during the rotation of the turntable 50. As a consequence, pinion 57 is blocked, whereby the follower ring 84 of the overload coupling 87 will be displaced in the downward direction by virtue of the vertical torque component upon the teeth 85, 86, resulting thereby in the interruption of the coupling connection between the ring 84 and gear 85 and actuation of the electrical contact device 101 by the lever 100 engaged by said ring, resulting in the operation of relay D4. As a consequence, the holding contact d40 of the relay D4 is closed, while the relay contact d41 is opened, to thereby interrupt the circuit of the coupling winding 90 and to, in turn, result in the decoupling of the drive shafts 81 and 91 and stoppage of the auxiliary driving motor 94.

Actuation of the contact device 101 furthermore has resulted in the closing of the relay contact (1'42 and setting into operation of the time-delay relays D41 and D42. Time-delay relay D41, which has a delay time being less than the delay time of the relay D42, at first closes, by way of the still closed contacts d11 and 0362, its own contact d411, and relay C3, the circuit of the main driving motor which, in turn, drives the two driving pinions 52, 57 in their original directions of rotation by way of the speed reduction unit 35. As a consequence, the driving pinion 57 again assumes, on the basis of the operating conditions of rotating gea-r mechanism, a position where the line connecting the centers of the pinions 52, 57 is at right angle to the tangent of the guide path at the engagement point of the pinions or gears, preparatory to the resumption of the operation of the stencil 26 for the sewing of the next following seam section. Since the turntable 50 is still in the lowered position, the pinion 52 engages the trailing pins 104 only, while being disengaged from the leading pins 103 of the corner section by virtue of the reliefs 105.

As soon as the pins 103, 104, representing the corner or angle of the seam or guide path are completely disen gaged from the pinion 52, a further cam (not shown) serves to actuate a switch NN which causes, by way of relay D2 and contact d23, the de-energization of the time delay relay D11 and interruption of the circuit of the solenoid 75 by way of contact 01111 of said relay. As a consequence, the spring 79 acts to return the drive shaft 49 together with the turntable 50 to the normal or upper position, to in turn result in the engagement of the pins 102 by the driving pinions in the original plane of engagement or position. At the same time, actuation of the switch NN has resulted in the de-energization of the relays D4 and D6, thus causing the de-energization of all the time-delay relays D11, D12, D41 and D42. Release of the relay D6 then results in the release or closing of the contact d61 and in turn in the energization of the motor 10 by way of the contacts d11, d21, c131, d51, and d61.

As soon as the point of the guide path 29 denoted by II in FIG. 3 reaches the two driving pinions 52, 57, cam 115 disposed upon the upper surface of the stencil carrier 27 actuates the contact device 116, thereby causing the operation of the relay D2, attraction of its holding contact d20 and release or opening of contact d21. As a consequence, the operating circuit of the motor 10 is interrupted, whereby to arrest the operation of the sewing machine with the needle in the work or DOWN-position. Inasmuch as the pin 108, opposite to the pin 107 in respect to the seam, has a relief 109 along the upper third of its length, the driving pinion 57 in position II, FIG. 3, of the stencil is in engagement with the pin 107 only, while being disengaged from the pin 108. Actuation of the contact device 116 results furthermore in the release or opening of contact d22 and closing of contact d24 of the relay D2, whereby the electromagnetic coupling K1 of the reduction unit 35, previously energized through contacts L122, (280 and d71 of the relay D8, becomes de-energized, while the hitherto de-energized coupling K2 of said unit becomes energized by way of contacts d35, d24, d81 and relay D7, whereupon restarting of the motor 10 results in the pinions rotating in a direction opposite to the previous direction of rotation. The safety contact d71 connected in the circuit of the relay R8 upon becoming de-energized ensures the energization of the coupling K2 coordinated with the relay D7. Operation of the relay D2 simultaneously results in the closing of contact d235, whereby to set into operation both time-delay relays D11 and D12. As a consequence, contact (1111 of relay D11 having a time relay less than the time delay of the relay D12 is closed, whereby to energize the solenoid 75 and to cause a downward displacement of the shaft 49 and turntable 50 by way of the forked head '74, follower ring 47, lever 61, pull bar 64 and lever 66. As a consequence, the driving pinion 52 assumes a position as shown in dot-dashed lines in FIG. 5 in which it engages both the pin 107 and 108, to thereby maintain the stencil in continuous form-locking engagement with said pinions. Subsequently, contact d121 of the relay D12 is closed, to energize the coupling winding by way of contacts d41 and d121. At the same time there is closed the circuit of relay C2 by way of contacts d41, d121, d25 and 011, to start rotation of the motor 94. Closing of the circuit of the relay C2 further causes the opening of the safety contact 021 inserted in the circuit of the relay C1, whereby to ensure the deenergization of relay C1 and the starting of the motor in a direction opposite to its preceding direction of rotation. Energization of the winding 90 results in the coupling of the shafts 81 and 91, whereby to rotate the turntable 50, in the direction of the arrow as shown at point II in FIG. 3, the extent of rotation of the turntable 50 and pinion 57 being again limited by the overload coupling 87, in the manner described hereinbefore and shown in dot-dash lines on FIG. 5.

Operation of the overload coupling 87 in turn results in the actuation of the contact device 101, whereby to energize the relay D4 by way of its holding contact d40 and to set into operation the time-delay relays D41 and D42 by way of contact (Z42, in the same manner as described previously. Opening of contact d41 of relay D4 results in the interruption of the circuits of both the coupling winding 90 and of the motor 94, while contact 412 of relay D41 is closed, to result in the energization of the solenoid 76 by way of the still closed contact 1'27 and, in turn, in the further operation of the drive shaft 49 together with the turntable 50 in the downward direction by an additional amount equal to the thickness of the pinions 52, 57 by Way of lever 61, pull bar 64 and lever 66, whereby the pinions 52, 57 assume the position at the end of the downward displacement more clearly shown in FIG. 6. Upon closing of the contact d412, contact d421 of the relay D42 is closed, whereby to energize relay C3 by way of contacts d11, Q26 and (1421 and to restart the motor 10. Inasmuch as the direction of rotatation of the output shaft 39 of the reduction gear unit 35 is opposed to its previous direction of rotation, as a result of the described action of relay D7, the required reversal of the direction of rotation due to the changeover of the guide path 29 or pinion 57, respectively, from one to the other side of the seam is achieved thereby. The driving pinion 52 in the position of FIG. 6 is completely disengaged from the pin 107, whereby the pinions 52, 57 rotating in directions opposite to the directions of rotation prior to their engagement by the guide path section II, FIG. 3, are enabled to successively engage the pins 108 and 110, to thereby continue the operation of the stencil. Shortly before the reaching by the pinions 52, 57 of the first pin 102 following the pin 110, a further cam disposed upon the carrier 27 (not shown) aetuates the switch or contact device NN, whereby to ale-energize the relay D2 and to in turn interrupt the circuit of the solenoid 76 by way of contact d27 opening at the same time. As a consequence, spring 79 acts to return the shaft 49 and turntable 50 to its normal or upper position, to result in the continued operation of the stencil 26 for the completion of the scam, in a manner readily understood. Opening of the relay D2 results in the opening of contact d26 and closing of contact d21, whereby to maintain the motor 10 in energized condition by way of contacts dll, d21, d31, a152, 4161 and relay C3. Opening of relay D2 is followed by the opening of relay D4, whereby to in turn de-energize all the time-delay relays D11, D12, D41 and D42.

Sewing of the second or outer corner of the seam at position III of guide path 29, FIG. 3, is substantially similar to the sewing of the first or inner corner at position I. More particularly, as soon as the driving pinion 52 assumes the relative position III in respect to the stencil, cam 111 disposed upon the upper surface of the carrier 27 actuates a further contact device 213 indicated only in the wiring diagram, FIG. 14, whereby to operate and attract the holding contact c150 of a further relay D5. As a consequence, contact c152 is opened, whereby to interrupt the circuit d11d21-d31d51-d6003 and to.arrest the driving motor 10 and with it the reduction gear unit 35 in the DOWN-position of the needle of the sewing machine, in substantially the same manner as described and understood from the foregoing. Since the pins 104 of the respective section of the guide path are again provided along their upper halves with reliefs 106, the driving pinion 52 in this relative position in respect to the guide path engages the pins 103 only forming part of the corner section of the stencil, whereby to enable the pinion to advance to a point where its axis coincides with the center of curvature of said section. Actuation of the contact device 213 furthermore causes the closing of contact c152 of the rely D and in turn the setting in operation of the time-delay relays D11 and D12. Upon expiration of the predetermined delay of the relay D11,

the latter causes attraction of its contact d111, whereby to result in the energization of the magnet or solenoid and, in turn, in the downward displacement of the shaft 4? and turntable 50 to an extent corresponding to the thickness of the pinions 52, 57, in the manner described and explained hereinbefore.

Subsequently, contact d121 of the relay D12 is closed, whereby to energize the coupling winding 99 by way of contacts d41 and d121. At the same time, relay C2 is energized by way of contacts a 41, d121, d53 and e11, to start motor 94 in the predetermined direction and to cause the turntable 50 to rotate in the direction of the arrow shown at point III, FIG. 3, whereby to displace the pinion 57 from the lower leg to the upper leg of the angle or corner, as indicated in dot-dashed lines in the drawing. Again, the safety contact 021 inserted in the circuit of the relay C1 ensures the starting of the motor 94 in the required direction. Rotation of the turntable 50 is again limited, as determined by the size of the angle, by the action of the overload coupling 87, by the displacement of the follower ring 84 actuating the contact device 101 and operating or energizing the relay D4 through its holding contact 46. As a consequence, contact 141 of the relay D4 is opened, whereby to de-energize the coupling winding as well as the relay C2, thereby in turn effecting the stoppage of the motor 94. Energization of relay D4 furthermore has resulted in the energization, by way of contact d42, of the two time-delay relays D41 and D42, whereby, upon further closing of contact d411, the circuit of motor 10 is closed by way of the contacts dll, c154 and d41, to re-start operation of the motor. Inasmuch as the driving pinion 52, as a. result of its downward displacement effected by the solenoid 75 and by virtue of the reliefs of the pins 103, is completely disengaged from the latter, and since the driving pinion 57 has assumed the position shown in dotdash lines at point III in FIG. 3, both pinions are again enabled to resume the normal operation of the stencil 26 in the manner described.

As soon as both pinions 52, 57 have been completely disengaged from the guide path section representing the angle or corner, a further cam (not shown) disposed upon the carrier 27 serves to actuate the switch NN, to in turn cause, as a result the release of the relay D5, the opening of contact d111 of the time-delay relay D11, thereby interrupting the circuit of the solenoid 75. As a consequence, the spring '7 9 acts to return the shaft 43 and turntable 56 to its normal or upper position, whereby to afford a renewed engagement between the pins 162 and pinions 52, 57 in the ordinary manner. Actuation of the switch NN further results in the de-energization of the relays D5 and D4, whereby to interrupt contacts d52 and 1141]., while closing, as a result of the closing of contact d51, the circuit d11d21-d31d51d61, to maintain the relay C3 in energized condition and, in turn, the operation of the motor 10, while returning all the contacts to their normal or inoperative position as shown in FIG. 14 of the drawings.

Referring to the embodiment of the invention as shown by FIG. 7, the drive shaft 49 journalled in the hollow shaft 44 again carries at its upper end a pin 51 which, compared with the pin 51 of the previously described embodiment, has an increased length and carries at its upper end the main driving pinion 52 being coaxial or in register with the needle 11 or stitching point, respectively, of the sewing machine. Pin 51 is journalled within a sleeve 157 which is in turn journalled in the upper part of the two-part turntable 50 having a central recess, for the purpose to be described in and understood from the following.

Mounted below the pinion 52 upon the pin 51 is a gear 53 which meshes with a counter gear 54 of equal pitch diameter. Gear 54 is secured to a pin 56 which is journalled in the upper part of the turntable 50 and carries at its upper end the auxiliary driving pinion 57. Both pinions 52 and 57 rotating in opposite directions again act as drive means of the pin rack or stencil and sewing goods carrier, respectively, in the manner described with reference to the first embodiment of the invention shown by the preceding figures of the drawings.

Secured to pin 51 below the gear 53 is a further gear 150 which meshes with a counter gear 152 by way of an intermediate gear 151 being journalled in the lower part of the turntable 51). Gear 152 is secured to a shaft 153 journalled in both parts of the turntable 50 and carrying at its upper end a further auxiliary driving pinion 154. Disposed above the gear 152 is a further gear 155 being secured to shaft 153 and meshing with a counter gear 156. The latter is secured to the sleeve 157 being journalled in the upper part of the turntable 50 and carrying at its upper end a further main driving pinion 158 being coaxial with the pinion 52 or needle 11, respectively. As a consequence, both further driving pinions 154 and 158 are driven in opposite directions, to wit with pinion 158 having a direction of rotation opposite to the direction of rotating of the main driving pinion 52 and the pinion 154, disposed at the opposite side of the seam, having a direction of rotation opposite to the direction of rotation of the auxiliary driving pinion 57, respectively. Both pinions 154 and 158, FIG. 8, are adapted to selectively engage, in the proper coupling position, one of the pins of the guide path 28 of the stencil 26, to displace the latter in substantially the same manner as the pinions 52, 57. The driving pinion pair 154, 158 has a greater diameter compared with the driving pinion pair 52, 57, whereby the guide path section 28, FIG. 8, has a corresponding greater distance from the seam or needle 11, the angular velocity of the pinion pair 154, 158 being, however, reduced in comparison with the angular velocity of the pinion pair 52, 57, by the proper design of the speed reduction ratio of the gears 150, 151, 152, in such a manner as to cause both pinion pairs to rotate with equal circumferential speeds.

The turntable 50 is again fitted at its lower end with gear teeth 80 which mesh with the gear 82 driven by the auxiliary motor 94 through the overload coupling 87. Projecting into the recess 98 of the follower ring 84 of the coupling 87 is one end of the lever 100, the opposite end of which cooperates with an electrical contact device 159 supported by a bracket 99 and serving, upon actuation, to interrupt the coupling winding 90, to re-start the motor 10 by way of a first time-delay relay, and to interrupt the circuit of the solenoid 76 by way of a second time-delay relay, respectively.

The stencil guide path having sections 28, 29, FIG. 8, determining the feed path of the sewing goods carrier, are disposed at the opposite sides in respect to the rotating axis of the driving pinions 52 and 158, the arrangement being such that the guide path section 28 serves for the sewing of the inner corner and the guide path section 29 serves for the sewing of the outer corner, respectively, of the seam, as shown in FIG. 8, it being understood that the change-over from one to the other path may be effected at any point between two differently oriented corners or angles to be sewn. The pins pertaining to the guide path or stencil section 29 substantially correspond to the pins 102, 103 and 104 of the previously described embodiment of the invention, while the pins 161, 162 and 163 pertaining to the section 28 have an increased length corresponding to the vertical distance between the pinions 52 and 158, but are otherwise equivalent to the pins 102, 103 and 104, respectively. Disposed at each of the corner points of the two guide paths and upon the upper surface of the stencil carrier 27 is a cam 111 cooperating with an electric contact device 160 supported by a bracket 112, said contact device serving, upon actuation, to arrest the motor 10 with the needle in the DOWN-position, to close, by way of a first time-delay relay, the circuit of the solenoid 76, and to close, by way of a second time-delay relay, the coupling winding 90, respectively.

The operation of the embodiment according to FIG. 7 will now be described in the following, under the assumption that it is desired to sew a seam as shown by the dashed line in FIG. 8 and that the preliminary conditions prevail as set forth in connection with the description of the embodiment according to FIG. 2.

During the sewing of the lower oblique section of the seam, FIG. 8, the driving pinions 52 and 57 being driven in opposite directions engage the pins 102 of the guide path 29 one at a time, whereby to impart a movement to the stencil 26 composed of polar coordinate elemental components, in the manner described hereinbefore. During the sewing of this seam section, pinions 154 and 158 are also driven in opposite directions relative to one another and to the respective pinions 52, 57, but are ineffective due to their disengagement from both the associated pins of the guide path 28 as well as from the pins of the guide path 29. As soon as the section of the guide path 29 corresponding to a seam corner or angle reaches the pinions 52, 57, said section embraces the pinion 52 to an extent until its center of curvature coincides with the axis of the pinion 52, and in turn, of the needle 11. At the same time, cam 111 actuates the contact device 160, resulting thereby in the arresting of the motor 10 with the needle in the DOWN-position, in the closing of the circuit of the solenoid 76 by way of a first time-delay relay, and in the closing of the circuit of the coupling wind ing by way of a second time-delay relay, respectively. The latter operations may be effected by suitable electrical control and switching means, substantially similar to the control circuit as shown by FIG. 14. As a consequence, shaft 49 together with the turntable 50 is lowered, by way of the lever 61, pull bar 64 and lever 66, by an amount corresponding to the thickness of the pinions 52, 57, whereupon pinion 57 is rotated from a position of engagement with the outer leg of the corner or angle to a position of engagement with the inner leg of said corner, in substantially the same manner as described hereinbefore, to assume a final or end position by the action of the overload coupling 87, the latter in turn causing the actuation of the contact device 159 by the lever 100. As a consequence, the circuit of the coupling winding 90 is interrupted and the motor 10 re-started by way of a first time-delay relay, whereby to again rotate the pinions 52 and 57 by way of the speed reduction unit 35, pinion 52 in the lowered position engaging pins 104 only due to the reliefs 105 of the pins 103 and continuing the movement of the stencil 26 whereupon, after the pins 104 have become completely disengaged from the pinion 52, actuation of the contact device 159 by the second time-delay relay causes the circuit of the solenoid 76 to be interrupted, whereby to allow the spring 79 to return the shaft 49 and turntable 50 to their upper or normal position. Again, during the sewing of this section of the scam, the pinions 154 and 158 are without effect upon the stencil 26, inasmuch as they rotate below the pins 102, as more clearly seen from FIG. 9 and, upon lowering of the pinions 52, 57, remain disengaged from the pins of the guide path 29.

As soon as the change-over point between the guide paths 28 and 29 reaches the pinion pairs 52, 57 and 154, 158, respectively, the latter relieve one another in the operation of the stencil. More particularly, during the entry of the change-over point into the two pinion pairs, the last pins 102 of the path 29 successively engage the pinion pair 52, 57 until the connecting line between the centers of the pinions is at right angle to the tangent of the guide path at the engagement point. Since, as seen from FIG. 8, the centers of the pinions 52 and 158 coincide with one another and since the center of the pinion 154 is located upon the prolongation of the connecting line of the centers of the pinions 52, 57, the connecting line of the centers of the pinion pair 154, 158 will also be normal to the tangent of the guide path section 28 being parallel to the guide path section 29. Since, furthermore, the pinion pair 154, 158 rotates with the same circumferential speed as but in opposite directions to the pinion pair 52, '7, and since the guide path 28 is located, in respect to the rotary axis of the pinions 52, 158 on the opposite side from the guide path 29, both pinion pairs 52, 57 and 154, 158 are enabled to briefly engage, at the change-over point, the associated guide paths 29 and 28, respectively, whereby to commonly effect the displacement of the stencil 26 until pin 102 pertaining to the guide path 29 has completely run off the pinion pair 52, 57. At the same time, the first two of the pins 161 pertaining to the guide path 28 have successively engaged the pinion pair 15 158, whereupon the latter assumes the operation of the stencil in accordance with the guide path 28, while the continued rotation of the pair 52, 57, remains ineffective, as far as the stencil movement is concerned, due to its disengagement from both guide paths 28 and 29.

As soon as the curved section of the guide path 28 corresponding to the second or right angular (in the example shown) corner of the seam has reached the pinions 154, 158, it engages the latter to an extent until its center of curvature coincides with the axis of the pinion 158. In this position in which the pinion 158, by virtue of the reliefs in the upper half of the pins 163, engages the two pins 162 only, cam 111 upon the stencil carrier 27 actuates the contact device 160, to thereby stop the motor with the needle in the DOWN-position, and to energize the solenoid 76 by way of a first time-delay relay. This in turn results, in the manner described hereinbefore, in the lowering of the turntable 50, whereupon at the same time the coupling winding 90 is energized by way of a second time-delay relay, to result in the coupling of the shafts 31 and 91. As a consequence, pinion 154, FIG. 8, is rotated in clockwise direction to an end position controlled by the overload coupling 87 such as to engage pin 163 of the guide path 28. Inasmuch as the direction of rotation of the turntable 50 for this section of the guide path 28 is opposite to the direction of rotation for the section 29, there is provided at this position of the guide path a further control cam (not shown) which by way of a further contact device (also not shown) serves to eflect, prior to the coupling of the shafts 81, 91, a reversal of the direction of rotation of the motor 90. The pinion 158 in its lowered position and as a result of the reliefs upon the lower parts of the pins 163, is disengaged from the latter, while being in engagement with the pins 163. The contact device 159 actuated by the overload coupling 87 has interrupted the circuit of the coupling winding 90 and closes, by way of a first time-delay relay, the circuit of the motor 10, thus again driving the pinions 158, 154, to thereby continue the displacement or operation of the stencil in the manner described and understood, whereupon, as soon as the pins 162, 163 have run completely off the pinion 158, the circuit of the solenoid 76 is opened by a second time-delay relay of the contact device. As a consequence, spring 78 acts to return the turntable 50 to its normal or starting position, in which the pinions 154, 153 resume the displacement of the stencil by engaging pins 161 in accordance with the configuration of the guide path 28.

In the embodiment of the invention shown by FIGS. 1-9, the stencil guide paths 28 and 29 are shown in the form of a pin rack being composed of a multiplicity of pin teeth disposed in mutually spaced relation along a trace conforming to the seam or pattern to be sewn. According to a modified embodiment of the invention, the guide path may be constructed of any equivalent means or elements, such, for instance, in the form of a wavy band or strip, as shown in perspective view in FIGS. 10 and 11. Referring to the latter, the guide path 201 is formed by the wavy or corrugated strip 200 being fitted with lugs 202 for mounting the same upon the underside of the stencil carrier or base plate 27 and driven by a pair of gears or driven by a pair of gears or driving pinions 203 and 204, FIG. 11, rotating in opposite directions relative to one another, in substantially the same manner as in the case of the pin rack of the preceding embodiments.

The driving pinions may be journalled, in the manner described, in the rotary turntable 50 displaceable in the 5 vertical direction, with the pinion 203 being coaxial with said table and the needle of the sewing machine, and with the pinion 204 being displaced laterally of the pinion 203. Besides, both pinions 203 and 204 are arranged in relative angular position such as to engage or embrace the strip 200 by a tooth of one pinion and by a gap of the other pinion, respectively, in the manner shown in FIG. 11, whereby to commonly drive the band or stencil 200 in a manner equivalent to the pin rack of the preceding figures. In order to enable the sewing of relatively sharp corners, in accordance with the invention, by means of a corrugated stencil of this type, the latter may be provided with suitable recesses at the point corresponding to the corners or angles of the seam. More particularly, in the example shown by FIG. 10 the portion of the path 201 corresponding to the horizontal part of the corner or angle, as indicated by the dashed line in the drawing, is provided at its lower part with slots or recesses 205, while the part corresponding to the oblique part of the corner is provided at its upper part with slot-like recesses 206 corresponding to the reliefs 205 and 206 of the pins 103, 104 of the preceding embodiments, FIGS. 1-9, respectively.

The operation of the stencil according to FIGS. 10 and 11 is substantially identical to the operation of the 30 preceding embodiment, in that for the sewing of the horizontal seam section of FIG. 10 the driving pinion 203 and 204 engage the stencil or guide path 201, to displace the same and with it the sewing goods carrier relative to the needle 11 in accordance with the configuration of the seam to be sewn, in the manner described and understood from the foregoing. As soon as the section of the path 201 corresponding to a corner of the seam reaches the pinions 203, 204, it embraces the latter to an extent until its center of curvature coincides with the axis of the 4g driving pinion 203, whereby the latter, due to the recess 206, is engaged with the horizontal portion only of the respective guide path section. In this position, both the sewing machine and the two pinions are arrested, followed by the lowering of the pinion 203 and rotation of the pinion 204, respectively, in the manner described. Inas much as the guide path section corresponding to the horizontal seam portion is provided at its lower part with recesses or slots 205, the pinion 203 in the lowered position is engaged with the guide path section pertaining to the oblique portion of the seam only, whereby to allow the latter to be readily disengaged from the pinion pair If it is desired to sew both inwardly and outwardly oriented corners or angles by the use of corrugated stencil or guide path 201, this may be achieved both by the provision of suitable change'over means from one to the other guide path and reversal of the direction of rotation of the driving pinions, as in FIG. 3, or by the provision of two pairs of driving pinions selectively cooperating with the stencil, in the manner described and understood from the foregoing.

In place of the corrugated stencil, it is furthermore possible to utilize a perforated strip cooperating with a pair of sprockets in the manner of a motion picture film transport. In order, in the latter case, to enable the sewing of both inner and outer corners or angles, all that will be necessary is the provision of extended recesses in place of the perforations, corresponding to the reliefs of the pin rack or slots of the corrugated stencil according to the previously described embodiments, whereby to again enable, in one plane of engagement of the sprockets, the ready entry of the strip into the main driving sprocket and disengagement therefrom, in the other plane of engagement, respectively.

In the foregoing the invention has been described, in

reference to a few specific illustrative devices or constructional embodiments. It will be evident, however, that variations and modifications, as well as the substitution of equivalent parts or devices for those shown for illustration, may be made without departing from the broader scope and spirit of the invention as set forth in the appended claims. The specification and drawings are ac cordingly to be regarded in an illustrative rather than in a restrictive sense.

We claim:

1. Automatic sewing apparatus comprising in combination:

(1) a sewing machine having a bed, an electric driving motor, and means including a reciprocatory needle operably connected with said motor, to sew stitches in a workpiece fed past said needle,

(2) a work carrier mounted upon said bed for both translatory displacement along a straight line and rotation about a pivot movable along said line,

(3) a driving stencil connected to said carrier being constituted by a multiplicity of mutually spaced driving elements forming a guide path conforming to the configuration of a seam to be sewn in the work supported by said carrier, said stencil including at least one corner section having leading and trailing legs in respect to the direction of movement of the stencil, said legs including an angle of 90 or less, for the sewing of a corresponding corner of said seam,

(4) a main driving pinion having a fixed axis with means to drive the same by said motor, said pinion arranged laterally of said stencil coaxially with said needle, to operably engage one side of said elements,

(5) a rotary support coaxial with said main driving pinion, and

(6) an auxiliary driving pinion rotatively mounted upon said support with means to drive the same by said motor in a direction opposite to the direction of rotation of said main driving pinion,

(7) said auxiliary driving pinion arranged to operably engage the opposite side of said elements and adapted to roll upon the circumference of said main driving pinion, or displacement of said auxiliary pinion from a position of engagement with the leading leg to a position of engagement with the trailing leg of said corner section by rotation of said support.

2. Automatic sewing apparatus as claimed in claim 1, including an auxiliary electric motor to drive said sup port, and electrical control and switching means operably interconnecting said driving motor, said auxiliary motor and said stencil, whereby to automatically elfect the sequential operations, in the order named, of arresting said main driving motor upon the corner section of the stencil embracing said main driving pinion at the end of the sewing of the leading leg of the corner of the seam, starting said auxiliary motor to rotate said auxiliary pinion about the corner of the stencil from its position of engagement with the leading leg to a position of engagement with the trailing leg of said corner, arresting said auxiliary motor and re-starting said main driving motor for the sewing of said trailing leg and the remaining portion of said seam.

3. In automatic sewing apparatus as claimed in claim 2,- including overload coupling means interposed between said auxiliary driving motor and said support, to arrest said auxiliary pinion upon reaching its position of engagement with the trailing leg of the stencil corner section 4. In automatic sewing apparatus as claimed in claim 2, said stencil including a pair of serially arranged straight and parallel sections preceding said corner section, said straight sections being spaced by a distance equal to the diameter of said main driving pinion, to cause said main pinion to change from its engagement with one of said straight stencil sections to a position of engagement with the other straight stencil section at the change-over point between said sections, and further electrical control means operably connected with said stencil, to rotate said auxiliary pinion by 180 from a position of engagement with the first straight stencil section to a position of engagement with the second straight stencil section, respectively, at said change-over point.

5. In automatic sewing apparatus as claimed in claim 2, said stencil having a pair of serially arranged parallel straight sections preceding said corner section, a second pair of main and auxiliary driving pinions in addition to said first pair of main and auxiliary pinions, the main driving pinions of both said pairs being coaxial and the auxiliary driving pinion of the second pair being rotative- 1y mounted upon said support diametrically opposite to the auxiliary driving pinion of the first pair, means to rotate the main and auxiliary driving pinions of the second pair by said driving motor in directions opposite, respectively, to the directions of rotation of the main and' auxiliary driving pinion of the first pair, said driving elements designed to cause the straight sections of the stencil to selectively cooperate with predetermined ones of said driving pinion pairs.

6. In automatic sewing apparatus as claimed in claim 1, said stencil consisting of a rack comprising a multiplicity of spaced rack pins, to cause the opposed gaps of said main and auxiliary driving pinions to engage opposed segmental areas of said pins.

7. In automatic sewing apparatus as claimed in claim 1, said stencil consisting of a corrugated strip with said pinions arranged on opposite sides of said strip, to cause each of the corrugations of the strip to be engaged by a tooth and intermediate gap of said pinions, respectively.

8. In automatic sewing apparatus as claimed in claim 1, including electrically controlled actuating means, to displace said pinions in the axial direction, the stencil elements forming a corner designed to elfect disengagement of said main driving pinion from the elements forming the trailing leg of said corner in the normal position of said pinions, and to efiect disengagement of said main pinion from the elements forming the leading leg of said corner in the axially displaced position of said pinions.

9. In automatic sewing apparatus as claimed in claim 8, including an auxiliary electric motor to drive said support, and electrical control and switching means operably interconnecting said driving motor, said auxiliary motor, said stencil and said actuating means, whereby to automatically elfect the sequential operations, in the order named, of arresting said main driving motor upon the corner section of the stencil embracing said main pinion at the end of the sewing of the leading leg of the corner, axially displacing said pinions, starting said auxiliary motor to displace said auxiliary driving pinion from its position of engagement with the leading leg to a position of engagement with the trailing leg of said section, arresting said auxiliary motor, returning said pinions to their normal position, and re-starting said driving motor for the sewing of the trailing leg of said corner and remaining portion of the seam.

10. In automatic sewing apparatus as claimed in claim 8, including overload coupling means interposed between said auxiliary motor and said support, to interrupt the coupling connection therebetween upon said auxiliary driving pinion reaching a position of engagement with the trailing leg of said corner, and further electrical control means operably associated with said overload coupling means, to arrest said auxiliary motor upon disengagement of said coupling means.

11. Automatic sewing apparatus comprising in combination:

(l) a sewing machine having a driving motor and means including a reciprocatory needle operably connected with said motor, to sew stitches in a workpiece fed past said needle,

(2) a movable work carrier displaceable along a straight line and rotatable about a pivot movable along said line,

(3) a driving stencil connected to said carrier being constituted by a multiplicity of mutually spaced driving elements forming a guide path conforming to the 1 configuration of a seam to be sewn in the work supported by said carrier, said stencil including a plurality of corner sections each having leading and trailing legs in respect to the direction of movement of said stencil, said legs including angles of 90 or less, for the sewing of corresponding corners of said seam, (4) a main driving pinion having a fixed axis with means to drive the same by said motor, said pinion arranged laterally of said path coaxially with said needle, to operably engage one side of said elements,

(5) a turntable coaxial with said first pinion,

(6) an auxiliary driving pinion rotatively mounted upon said turntable with means to drive the same by said motor in a direction opposite to the direction of rotation of said main driving pinion,

(7) said auxiliary pinion arranged to operatively engage the opposite side of said stencil and adapted for rolling displacement, by rotation of said turntable, upon the circumference of said main pinion from a position of engagement with the leading leg to a position of engagement with the trailing leg of a corner section of said stencil, and

(8) change-over means between at least one pair of corner sections of said stencil, including a pair of serially arranged straight parallel stencil sections on opposite sides of the seam being sewn, to change from a position of engagement of said main driving pinion with one side of said stencil to a position of engagement of said main pinion with the opposite side of the stencil.

12. In automatic sewing apparatus as claimed in claim 11, said last means consisting in said straight stencil sections being spaced by a distance equal to the diameter of said main driving pinion, to cause said main driving pinion to change from its position of engagement with one of said straight stencil sections at the change-over point to a position of engagement with the other straight stencil section, and further electrical control means operably connected with said stencil, to rotate said auxiliary pinion by 180 from a position of engagement With said first straight stencil section to a position of engagement with the second straight section of said stencil at the change-over point.

13. In automatic sewing apparatus as claimed in claim 11, said last means comprising a second pair of main and auxiliary driving pinions in addition to said first pair of main and auxiliary pinions, the main driving pinions of both said pairs being coaxial and the auxiliary driving pinion of the second pair being rotatively mounted upon said turntable diametrically opposite to the auxiliary driving pinion of the first pair, means to rotate the main and auxiliary driving pinions of the second pair by said main driving motor in directions opposite, respectively, to the directions of rotation of the main and auxiliary driving pinion of the first pair, the driving elements of said first and second straight stencil sections being designed to selectively cooperate with a predetermined one or" said driving pinion pairs, respectively.

14. In automatic sewing apparatus as claimed in claim 13, said driving elements being in the form of pins forming a rack cooperating with said pinions, the pins pertaining to one straight stencil section having a length difierent from the length of the pins pertaining to the other stencil sections, to cause said sections to selectively cooperate with difierent ones of said pairs of driving pinions, respectively.

References Cited UNITED STATES PATENTS 2,474,406 6/ 1949 Tillett et al 112102 2,552,350 5/1951 Smith. 2,880,683 4/1959 Abel 1l22 3,001,489 9/1961 Bond et al l12-102 X FOREIGN PATENTS 255,116 4/ 1963 Australia.

JORDAN FRANKLIN, Primaly Examiner.

I. R. BOLER, Assistant Examiner. 

1. AUTOMATIC SEWING APPARATUS COMPRISING IN COMBINATION: (1) A SEWING MACHINE HAVING A BED, AN ELECTRIC DRIVING MOTOR, AND MEANS INCLUDING A RECIPROCATORY NEEDLE OPERABLY CONNECTED WITH SAID MOTOR, TO SEW STITCHES IN A WORKPIECE FED PAST SAID NEEDLE, (2) A WORK CARRIER MOUNTED UPON SAID BED FOR BOTH TRANSLATORY DISPLACEMENT ALONG A STRAIGHT LINE AND ROTATION ABOUT A PIVOT MOVABLE ALONG SAID LINE, (3) A DRIVING STENCIL CONNECTED TO SAID CARIER BEING CONSTITUTED BY A MULTIPLICITY OF MUTUALLY SPACED DRIVING ELEMENTS FORMING A GUIDE PATH CONFORMING TO THE CONFIGURATION OF A SEAM TO BE SEWN IN THE WORK SUPPORTED BY SAID CARRIER, SAID STENCIL INCLUDING AT LEAST ONE CORNER SECTION HAVING LEADING AND TRAILING LEGS IN RESPECT TO THE DIRECTION OF MOVEMENT OF THE STENCIL, SAID LEGS INCLUDING AN ANGLE OF 90* OR LESS, FOR THE SEWING OF A CORRESPONDING CORNER OF SAID SEAM, (4) A MAIN DRIVING PINION HAVING A FIXED AXIS WITH MEANS TO DRIVE THE SAME BY SAID MOTOR, SAID PINION ARRANGED LATERALLY OF SAID STENCIL COAXIALLY WITH SAID NEEDLE, TO OPERABLY ENGAGE ONE SIDE OF SAID ELEMENTS, (5) A ROTARY SUPPORT COAXIAL WITH SAID MAIN DRIVING PINION, AND (6) AN AUXILIARY DRIVING PINION ROTATIVELY MOUNTED UPON SAID SUPPORT WITH MEANS TO DRIVE THE SAME BY SAID MOTOR IN A DIRECTION OPPOSITE TO THE DIRECTION OF ROTATION OF SAID MAIN DRIVING PINION. 